ABC has scrubbed plans for its first live musical in years, based on parent Disney's The Little Mermaid.

The event, announced in May and scheduled to air Oct. 3, a week into the new TV season, has been quietly postponed (and most likely canceled) due to budget constraints, according to people familiar with the decision who were unauthorized to speak publicly.

But the network, which confirmed the move Thursday without disclosing a reason, already had spent a considerable sum building sets, and was due to begin rehearsals soon.

The beaching of Mermaid marks the second cancellation of a live fall musical amid a crowded field: NBC in May tabled plans for Bye, Bye Birdie, its fifth planned holiday musical that was to star Jennifer Lopez, but NBC Entertainment chairman Robert Greenblatt says he hopes to revisit the project in late 2018, "if we can get back into JLo's scheduling vortex." (She has a Las Vegas show and stars in NBC's Shades of Blue and World of Dance.)

Carrie Underwood as Maria in NBC's 'The Sound of Music Live,' which started the recent live-musical trend.(Photo11: Will Hart, NBC)

Although NBC's The Sound of Music garnered big ratings (if not critical praise), the recent spate of live musicals have met with diminishing returns, and their expense — easily $20 million or more — is a barrier, especially since there's little market for reruns, DVD sales or streaming revenue.

"It's never been easy to make money" on these projects, Greenblatt says. "They're expensive to produce, and they really aren't great business prospects. We just (do) them because they're events."

NBC still plans Jesus Christ Superstar April 1, and Fox has two projects in its pipeline: A Christmas Story, based on the film and Broadway musical, promised for late this year, and Rent in 2018. NBC also has a play, Aaron Sorkin's A Few Good Men, announced for next spring.